Sitting high above Coire an t-Sneachda, we’ve just done my first multi-pitch for years: Pygmy Ridge. I didn’t enjoy it. It should have been easy for me. Lonely at the belay ledges and confused by the loose rocks I vented my frustration at my partner.
We sit to eat lunch, deciding to not do a second climb, and I take out my sketchbook, trying to make something of the day. As the clouds race across the sky the light changes, revealing differences with each break. The rocks seem to speak, and I colour their story through my brush.
Close up on the climb, nose next to the rock, the minerals merged into a seemingly homogeneous mass. But now, looking out over the coire to the ridge, I see all the colour gradients in the granite, first grey, then purple, red and blue. On the page the wet pigment bleeds together and dries quickly.
The Cairngorms formed when continents collided and closed the ancient Iapetus Ocean 500 million years ago. Forced down into the hot mantle, the oceanic plate melted, and buoyant magma rose through the crust becoming trapped in pockets beneath the surface. As it cooled the minerals grew into the dense grey granite: milky quartz, peachy feldspar, shiny metallic mica and dark specs of amphibole. The rocks that the granite touched were changed, too, sea floor sediments baked and folded in the heat, creating an aureole around the intrusion of shattered rock. At Stonehaven on the edge of the intrusion you find ripples at the edges of the granite, where the fudgy magma took the shape of the crinkled shale cases as it cooked them.
With time the rocks cooled and contracted, fractures splitting the granite rock vertically and horizontally all the way deep underground and leaving the metasediments brittle and breaking. On the crags the water and ice has rubbed the boulders loose from each other, friction forming rounded holds, and often something that looks very stable gives a good wobble.
Along Fiacaill Ridge the skyline is cut by vertical fractures, sweeping round and folding into Fiacaill Buttress. Picked out by dark shadows with thin, steady movements of the tip of my brush. Melting ice ages and rainfall have filled up the complex network of fractures with water, which is heated by radiogenic minerals in the granite creating an energy-rich source.
Eventually, we head down the hill to the car and are caught in an intense downpour that quickly pools on the surfaces. I’m relieved we didn’t do the second climb.